PGA Championship: Jason Day surges to second as Rory McIlroy leads by a shot at Valhalla

Top-ranked Rory McIlroy birdied two of his last three holes on Saturday morning to fire a 4-under-par 67 and grab a two-stroke lead in the rain-hit second round of the PGA Championship.

But Australia's Jason Day is in hot pursuit after firing a round-of-the-day 6-under 65 to sit in a tie for second place, just a shot behind McIlroy.

Day made a sizzling start to his second round, shooting three birdies and an eagle in his first nine holes.

A run of six consecutive pars from the ninth to the 14th hole, and then a bogey on the 15th, saw Day drop back momentarily, before he birdied the 17th and 18th to regain his momentum to sit at 8-under overall.

Day is level with USA's Jim Furyk, who hit five birdies in a second round 68.

"I played great," said the world number nine, who eagled the seventh after hitting a one-iron from 250 yards to 10 feet and sinking the putt.

"I got off to a great start, but the last thing that I expected to shoot was 30 on the front nine.

I got off to a great start, but the last thing that I expected to shoot was 30 on the front nine.

Jason Day

"I put some good shots together out there to give myself the opportunities to really take advantage of the front nine.

"Obviously the back nine is just a little tougher. I was a little disappointed that I had one bogey on the back nine but I came home strong with a couple of birdies, at 17 and 18."

Adam Scott was briefly in danger of missing the cut, after trading two birdies for two bogeys, before hitting a clean final nine holes to move to 2-under overall in 26th place.

Matt Jones (3-under) slipped to a tie for 17th spot after firing an even-par second round, while Geoff Ogilvy (2-under) is further back in a tie for 25th alongside Scott after hitting an even 71.

McIlroy, who began on the back nine, stumbled early with a bogey at the 12th but answered with birdie putts of 12 feet at the 13th and 16 feet at the 15th.

The three-time major winner left his second shot 32 feet short of the pin at the par-five 18th but holed a putt from there to move atop the leaderboard for the first time.

Another bogey at the second allowed USA's Ryan Palmer to match him with a birdie-birdie finish, but the 25-year-old Northern Ireland star smashed a 5-wood shot 243 yards to eight feet and birdied the par-five seventh, then closed with a 16-foot birdie putt at nine.

"I can't wait until tomorrow to get back on the course and do the same thing all over again," McIlroy said.

"I'm just going to try and keep the pedal down and get as many ahead as possible."

Americans Rickie Fowler (66) and Palmer (70), and Finland's Mikko Ilonen (68) were a further stroke back behind Day and Furyk.

Five-times major winner Phil Mickelson (67) was next best on a high-quality leaderboard, level at 6-under with Austrian Bernd Wiesberger (68).

England's former world number one Lee Westwood (72), fourth-ranked Swede Henrik Stenson (71) and American Steve Stricker (68) were among a group of seven players knotted at five under.

McIlroy enjoys superb follow-up to WGC win

McIlroy, whose other major wins include the 2011 US Open and 2012 PGA Championship, became the clear favorite this week with his first World Golf Championships title last Sunday in Akron, Ohio.

He could become the first man since Padraig Harrington at the 2008 British Open and PGA to win back-to-back major titles and could join Woods and Mickelson as the only male golfers in the last quarter-century with wins the week before they won a major.

"It would be huge," McIlroy said. "But there's a lot of golf left to play."

Palmer moved to 7-under overall after firing a 1-under 70, teeing off in a heavy downpour that caused a 45-minute delay, but not before he was forced to hit two shots into the water-logged 7,458-yard layout.

"It was tough when we teed off," Palmer said. "Wasn't quite sure if we should have teed off to be honest. You could barely see the fairway.

"We were questioning in the fairway why we had to hit into a puddle because (hole) one was already underwater. We were questioning why we have to hit a second shot into a green that's already half in standing water.

"They said, that's just golf. We're like, tell the guy indoors that's making the decision to come check it out, because it's wet."

"When we got to one green, we couldn't get a clean lie with the standing water. They couldn't even squeegee it clear enough."

Thailand's Kiradech Aphibarnrat and American Ben Crane, who each opened on 74, withdrew due to injuries.

Kiradech was troubled with a sore knee while a bad back made Crane the fourth US player to pull out.